// key-value 模型
public class HashBucket {
    private static class Node {
        private int key;
        private int value;
        Node next;


        public Node(int key, int value) {
            this.key = key;
            this.value = value;
        }
    }


    private Node[]  array;
    private int size;   // 当前的数据个数
    private static final double LOAD_FACTOR = 0.75;
    private static final int DEFAULT_SIZE = 8;//默认桶的大小

    public int put(int key, int value) {
        int index=key%array.length;
        Node cur=array[index];
     /*   if(cur==null){
            array[index]=new Node(key,value);
            size++;
            return value;
        }*/
        while(cur!=null) {
            if (cur.key == key) {
                int oldValue = cur.value;
                cur.value = value;
                return oldValue;
            }
            cur=cur.next;
        }
        Node node =new Node(key,value);

            //头插法
            node.next=array[index];
            array[index]=node;
            size++;
            if(loadFactor()>=0.75){
                resize();
            }
            return value;
    }
    private void resize() {
        Node[] newArray=new Node[array.length*2];
        for (int i = 0; i < array.length; i++) {
            Node cur=array[i];
            while(cur!=null){
                int index=cur.key%newArray.length;
                Node curNext=cur.next;
                cur.next=newArray[index];
                newArray[index]=cur;
                cur=curNext;
            }
        }
        array=newArray;

    }


    private double loadFactor() {
        return size * 1.0 / array.length;
    }


    public HashBucket() {
       array=new Node[DEFAULT_SIZE];
    }


    public int get(int key) {
         // write code here
        int index=key%array.length;
        Node cur=array[index];
        while(cur!=null){
            if(cur.key==key){
                return cur.value;
            }
            cur=cur.next;
        }
        return -1;
    }
}